The present invention relates to a synchronous machine having a salient pole rotor.
A method and an arrangement for reducing at least one frequency component of a periodic pulsation is described in European Patent No. EP-A1-0 268 160. In this arrangement, a synchronous generator is driven by a drive motor. Particularly a high-power synchronous generator driven by a diesel engine, and pulsations of an electrical quantity are compensated at the output of the synchronous generator with a frequency that deviates from the synchronous generator's own frequency. The control is effected on the path formed by the diesel engine, generator and power system by intervening in the excitation of the generator (i.e., by controlling the direct-axis magnetic field) or by influencing the operating conditions of the diesel engine (quantity and timing of the fuel injection are controlled), or by an impedance (adjustable additional load) arranged at the output of the generator. These types of control are costly, since in some circumstances one of these measures is not sufficient by itself to achieve a complete compensation of the periodic pulsation.
An object of the present invention is to provide a synchronous machine of the type mentioned above, in which the effects of mechanical oscillations of the salient pole rotor, which can be attributed to influences both on the drive side and on the load side, are compensated in a simple manner.